Is Duo MFA considered safe to use?

I know it’s not recommended on PG, but still asking for my use case.

I just saw that the NY Times recommends it, so wouldn’t mind trying it out but wanted to check whether it’s safe enough to try first.

Would be helpful to know your use case for such, if it isn’t recommended by PrivacyGuides. If not, It would be defacto-considered as not recommended due to being closed-source in nature, and recommended options are better.

which is…?